Homeschooling publisher's have absolutely nailed producing better and more engaging History, Science and Math curriculum. If you take public school curriculum history curriculum and compare it to a homeschool history curriculum the differences are instantly obvious. The homeschool curriculum is typically much more engaging, explores the topics deeply and typically they use alot of whole books and good literature. They make history fun, and therefore the kids absorb more of the information. It is presented in a 'hands on way', that will appeal to a variety of learning styles. The same applies to Science and Math.
But I have been disappointed in Language Art curriculum. To be clear, the curriculum currently on the market cover the fundamentals of Language art and the grammar or spelling parts of the curriculum can be innovative. But the problem is in the literature part of the programs... its dry, and slightly boring. So much really good children's literature has been produced in the past twenty years, but none of it appears in any of the programs. Its almost antiquated. The older classics of children's literature should appear in a good literature program, but there surely is room for more innovative, recent literature as well.
I went to the SETHSA conference trying to hunt down a LA program I could live with, and was dissapointed. Unless I stumble across one at the THSC in August, I am probably left to write my own curriculum again over this next year.